Packaged Gas Heating/
Electric Cooling Units
A Guide To Operating and Maintaining Your
Gas Heating/Electric Cooling Unit
48GS,GX
NOTE TO INSTALLER
This manual should be left with the equipment owner.
FOR YOUR SAFETY
Do not store or use gasoline or other
flammable vapors and liquids in the vicin-
ity of this or any other appliance.
Improper installation, adjustment, alteration, serv-
ice or maintenance can cause injury or prop-
erty damage. Refer tothis manual. For assistance
or additional information, consult a qualified in-
staller, service agency, or the gas supplier.
FOR YOUR SAFETY
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not
use any phone in your building.
• Immediately call your gas supplier from
a neighbor's phone. Follow the gas sup-
plier's instructions.
• If you cannot reach your gas supplier,
call the fire department.
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Before performing recommended maintenance,
be sure gas supply and main power switch to
unit are turned off. Electrical shock could cause
personal injury.
Model 48GS with Standard Wire Grille
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 101 Catalog No. 534-80132 Printed in USA Form OM48-18 Pg 1 1-03 Replaces: 48GS,GX-1SO
Model 48GX with Optional Louvered Grille
Your combination heating/cooling unit is equipped with
mlautomatic direct spark ignition and power combustion blower.
TO LIGHT UNIT
1. Do not mm off the electrical power to unit without
first mining off the gas supply.
2. Before attempting to start the gas heating section, fa-
miliarize yourself with all the procedures that must
be followed.
If you do not follow these instructions exactly, a fire or
explosion may result, causing property damage, injury,
or loss of life.
Refer to Fig. 1. See Fig. 2 for location of gas valve. Refer
to Fig. 3 while proceeding with the following steps.
Step 1 -- Set the telnperamre selector on room thermo-
stat to the lowest temperature setting and set system switch
to HEAT.
FRONT
ACCESS
PANEL
Fig. 1 -- Gas Heating/Electric Cooling Unit
(Unit 48GS Shown)
Step 2 --
Step 3 --
Step 4 --
Close the external manual shutoff valve.
Turn off the electrical supply to the unit.
Remove the front access panel with a 5/16-in.
nut driver.
Step 5 -- Move the selector switch on the internal gas
valve to the OFF position and wait 5 minutes.
Step 6 -- Move the selector switch on the intemat gas
valve to the ON position.
Step 7 -- Replace the fiont access panel.
Step 8 -- Turn on the electrical supply to unit.
Step 9 -- Open the external manual shutoff valve.
Step 10 -- Set the temperature selector on room thermo-
stat slightly above room telnperamre to start unit. The induced-
draft combustion-air tan will start. Main gas valve will open
and main burners should ignite within 5 seconds. If the burner
does not light within 5 seconds, the ignition module will go
into a Retry mode after a period of approximately 22 sec-
onds (t\_tlowing the 5-second ignition period).
If the burners do not light within 15 minutes of the initial
call for heat, there is a lockout.
Step 11 -- Set the temperature selector on room ther-
mostat to desired setting.
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1. If the main burners tail to light, or the blower i_aits
to start, shut down gas heating section and call your
dealer for service.
2. Never attempt to manually light the main burners on
unit with a match, lighter, or any other flame. If the
electric sparking device fails to light the lnain bum-
ers, refer to the t\_llowing shutdown procedures, then
call your dealer as soon as possible.
Failure to follow these requirements could result in serious
personal injury.
TO SHUT UNIT OFF
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Do not turn off the electrical power to unit without first
turning off the gas supply.
Failure to t\_ltow these procedures can result in serious
fire or personal injury.
NOTE: If unit is being shut do,a_ because the heating sea-
son has ended, make sure to turn on power to cooling
system.
If unit is being shut down because of a malfunction, call
your dealer as soon as possible.
Should overheating occur or the gas supply fail to shut
oft; shut off the manual gas valve to the unit before shutting
off the electrical supply.
Do not use this unit if any part has been under water. Im-
mediately call a qualified service technician to inspect the
unit and to replace any part of the control system and any
gas control which has been under water.
Refer to Fig. 4 while proceeding with the following steps.
Step 1 -- Set the temperature selector on room thermo-
stat to lowest temperature setting and set system switch to
OFF.
Step 2 -- Close the external manual shutoff valve.
Step 3 -- Turn offthe electrical power supply to the unit.
Step 4 -- Remove the front access panel.
Step 5 -- Move the selector switch on the internal gas
valve to the OFF position.
Step 6 -- Replace the burner access panel.
Step 7 -- Restore electrical power to the unit and set sys-
tem switch to COOL to ensure operation of the cooling sys-
tem during the cooling season.
ROUTINE MAINTENANCE
All routine maintenance should be handled by skilled, ex-
perienced personnel. Your dealer can help you establish a
standard procedme.
For your safety, keep the unit area clear and free of com-
bustible materials, gasoline, and other flamlnable liquids and
vapors.
To assure proper functioning of the unit, flow of combus-
tion and ventilating air must not be obstructed fiom reaching
the unit. Clearance of at least 30 in. is required on all sides
except the duct side.
MAINTENANCE AND CARE FOR THE
EQUIPMENT OWNER
Before proceeding with those things you might want to
maintain yoursell; please carefully consider the t\_llowing:
1. TURN OFF GAS SUPPLY AND ELECTRICAL
POWER TO YOUR UNIT BEFORE SERVICING
OR PERFORMING MAINTENANCE.
2. Do not turn off electrical power to this unit without
first turning off the gas supply.
3. When removing access panels or performing main-
tenance functions inside your unit, be aware of sharp
sheet metal parts and screws. Although special care
is taken to reduce sharp edges to a minilnum, be ex-
tremely careful when handling parts or reaching into
the unit.
Air Filters -- Air filter(s) should be checked at least ev-
ery 3 or 4 weeks and changed or cleaned whenever it be-
comes dirty. Dirty filters produce excessive stress on the blower
motor and can cause the motor to overheat and shut do,am.
Table 1 indicates the correct filter size for your unit. Refer
to Fig. 5 to access the filter(s).
To replace or inspect filter(s) (or accessory filter rack when
supplied):
1. Remove the filter access panel using a 5/16-in.nut driver.
2. Relnove the filter(s) by pulling the filter(s) out of the unit.
If the fitter(s) is dirty, clean or replace with new one.
When installing the new filter(s), note the direction of the
ail_ow arrows on the filter fiame.
If you have dit_cutty in locating your air filter(s), or if
you have questions concerning proper filter maintenance, con-
tact your dealer for instructions. When replacing filters, al-
ways use the same size and type of filter that was supplied
originally by the installer.
Never operate your unit without filters in place. Failure
to heed this warning may result in damage to the blower
motor and/or compressor. An accumulation of dust and
lint on internal parts of your unit can cause loss of ef-
ficiency and, in some cases, fire.
Heat Exchanger-- To ensure dependable and efficient
heating operation, the heat exchanger should be checked by
a qualified maintenance person before each heating season,
and cleaned when necessary. This checkout should not be
attempted by anyone not having the required expertise and
equipment to properly do the job. Checking and/or cleaning
the heat exchanger involves removing the gas controls as-
sembly and the flue collector box cover and, when com-
pleted, reinstalling the gas controls assembly for proper op-
eration. Also, the flue collector box cover must be replaced
correctly so that a proper seal is maintained. Contact your
dealer t\_r the required periodic maintenance.
Fans and Fan Motor -- Periodically check the con-
dition of tan wheels and housings and fan-motor shaft
bearings. No lubrication of condenser- or evaporator-fan
bearings or motors is required or recommended.
Evaporator and Condenser Coils -- Cleaning of
the coils should only be done by qualified sel_ice per-
sonnel. Contact your dealer for the required annual
maintenance.
Condensate Drain -- The drain pan and condensate
drain line should be checked and cleaned at the same time
the cooling coils are checked by your dealer.
Compressor-- All compressors are tZactory-shippedwith
a normal charge of the correct type refrigeration grade oil in
them and should rarely require additional oil. The service
person must be certain the proper oil level is maintained in
the compressor when it is installed and running.
Condenser Fan
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Do not poke sticks, screwdrivers, or any other object
into revolving fan blades. Severe bodily injury may
result.
The tan must be kept fiee of all obstructions to en-
sure proper cooling. Contact your dealer for any required
selMce.
Table 1 -- Indoor-Air Filter Data*
UNIT SIZE
48GS018-030
48GS036-042
48GS048-060
48GX024-030
48GX036
48GX042-060
*Forfilter grille installations only.
FILTER SIZE
20x20
20x24
24x30
20x20
20x24
24x30
BURNERS GAS VALVE HOOD
Fig. 2 -- Gas Heating/Electric Cooling Unit